%0 Journal Article %T The presence of phosphorylation form of D1 protein in its cross-linked aggregates in high light treated spinach leaves in vivo %A Huimin Wei %A Junwei Guo %A Shuang Zhang %A Bo Huang %A Yinqiu Liu %A Linfang Du %J Chinese Science Bulletin %@ 1861-9541 %D 2006 %I %R 10.1007/s11434-005-1529-3 %X In the present study, using specific antibody against D1 protein, we detected four aggregates of D1 protein in thylakoid membranes from spinach leaves illuminated at high light (800¨C2500 ¦̀mol photons¡¤m 2¡¤s 1) for 3 h. Their accumulations were dependent on the light intensity to which the leaves had been subjected. Further immunoblot analysis indicated that 70 kD aggregate was a product of D1 protein cross-linked with CP43, 65 and 60 kD aggregate were two cross-linked products between D1 and D2 proteins, and 41 kD aggregate was one cross-linked D1 with ¦Á-subunit of cytochrome b 559 (Cyt b 559). This result provided the evidence for the existence of the aggregation of the D1 protein in vivo. The maximal level of D1/Cyt b 559 aggregate occurred at 1000 ¦̀mol photons¡¤m 2¡¤s 1 but drastically decreased with further increasing light intensity. Immunoblot analysis with phosphothreonine (Thr (P)) antibody indicated that D1/CP43 and D1/Cyt b 559 aggregates contained the phosphorylated protein(s). In vitro dephosphorylation experiment also showed that D1/Cyt b 559 and D1/CP43 aggregates lost the immunoreactivity with Thr (P) antibody after the phosphatase treatment of the membranes from high-light-illuminated leaves. Our results demonstrated that strong illumination of spinach leaves induced cross-linked products of D1 protein with its nearby polypeptides of PS, some of which co.n-tained the phosphorylated D1 protein. %K D1 protein %K phosphorylation %K cross-linking %K aggregation %K photoinhibition %K leaves %K CP43 %K cytochrome b 559 %U http://link.springer.com/article/10.1007/s11434-005-1529-3